/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.log4j.lf5.viewer.categoryexplorer;

import org.apache.log4j.lf5.LogRecord;
import org.apache.log4j.lf5.LogRecordFilter;

import java.util.Enumeration;

/**
 * An implementation of LogRecordFilter based on a CategoryExplorerModel
 * 
 * @author Richard Wan
 */

// Contributed by ThoughtWorks Inc.
public class CategoryExplorerLogRecordFilter implements LogRecordFilter {
	//--------------------------------------------------------------------------
	// Constants:
	//--------------------------------------------------------------------------

	//--------------------------------------------------------------------------
	// Protected Variables:
	//--------------------------------------------------------------------------

	protected CategoryExplorerModel _model;

	//--------------------------------------------------------------------------
	// Private Variables:
	//--------------------------------------------------------------------------

	//--------------------------------------------------------------------------
	// Constructors:
	//--------------------------------------------------------------------------

	public CategoryExplorerLogRecordFilter(CategoryExplorerModel model) {
		_model = model;
	}

	//--------------------------------------------------------------------------
	// Public Methods:
	//--------------------------------------------------------------------------

	/**
	 * @return true if the CategoryExplorer model specified at construction is
	 *         accepting the category of the specified LogRecord. Has a
	 *         side-effect of adding the CategoryPath of the LogRecord to the
	 *         explorer model if the CategoryPath is new.
	 */
	public boolean passes(LogRecord record) {
		CategoryPath path = new CategoryPath(record.getCategory());
		return _model.isCategoryPathActive(path);
	}

	/**
	 * Resets the counters for the contained CategoryNodes to zero.
	 */
	public void reset() {
		resetAllNodes();
	}

	//--------------------------------------------------------------------------
	// Protected Methods:
	//--------------------------------------------------------------------------

	protected void resetAllNodes() {
		Enumeration nodes = _model.getRootCategoryNode()
				.depthFirstEnumeration();
		CategoryNode current;
		while (nodes.hasMoreElements()) {
			current = (CategoryNode) nodes.nextElement();
			current.resetNumberOfContainedRecords();
			_model.nodeChanged(current);
		}
	}
	//--------------------------------------------------------------------------
	// Private Methods:
	//--------------------------------------------------------------------------

	//--------------------------------------------------------------------------
	// Nested Top-Level Classes or Interfaces
	//--------------------------------------------------------------------------
}
